Which statement best describes derivative-use immunity?

• A. It prohibits use of the witness's testimony and any evidence derived from it in prosecuting the witness
• B. It grants immunity from all prosecutions
• C. It prevents the witness from being compelled to testify
• D. It only protects civil liability

Answer: (D)

Derivative-use immunity means the government cannot use a witness’s compelled testimony or any evidence derived from that testimony against the witness in a criminal prosecution. That protection targets prosecutions that rely on the compelled testimony’s fruits, and it does not shield the witness from civil liability. It also doesn’t make the witness untestifiable by itself—the witness can be compelled to testify in exchange for immunity, but the government must avoid using the immunized testimony or its derivative evidence in related criminal prosecutions. So the statement that best captures this is that derivative-use immunity prohibits use of the witness’s testimony and any evidence derived from it in prosecuting the witness. The other ideas overstate or misstate the scope: it isn’t immunity from all prosecutions, it isn’t a blanket privilege against testifying, and it doesn’t limit protection to civil liability.